单选题

You are the administrator of a Junos Pulse Access Control Service implementation. You must restrict authenticated users connected from the branch offices to a few specific resources within the data center. However, when the authenticated users are connected at the corporate office, they are allowed more access to the data center resources. You have created two roles with different levels of access and are trying to determine the best way of controlling when a user is mapped to a specific role. Having the user prompted to manually select their role is possible, but you want to automate the process. Which configuration solves this problem?（）

A Implement a RADIUS request attribute policy to assist with realm selection and create different role-mapping rules for the user in each realm.

B Implement a directory/attribute server on the realm and set up this server to determine by group membership the proper role to which a user should be mapped.

C Reorder the role-mapping rules to allow for the more open role to be mapped first and then enable the stop processing rules when this rule matches function on this role.

D Implement a Host Checker policy on the realm that determines the geographic location of the device and restricts the user based on the results of the policy.